I can't make female friends

I'm a 21 year old female and I haven't had a female friend since high school. I was 16 years old the last time I made a new friend who was a girl, and I've only had five close female friends over the course of my life. I'm longing for close relationships with other girls but I always feel so awkward around them. For years I have only been able to be friends with boys/men because I feel so much more confident around them and find them easier to talk to. I'm starting to suspect that I only feel socially confident around people who I suspect could be attracted to me. This makes me ashamed of myself, but I guess somehow I must have developed the idea that people can only be genuinely interested in talking to me if they're attracted to me. I always get the feeling that when girls talk to me it's not because they actually want to, but because they are just being nice. Can anyone relate to this feeling? Has anyone overcome this? Just wanted to share...

When I was growing up, I was more outgoing then most girls. I was not afraid to talk to anyone...Unfortunately my Queen of Queen attitudes led to overconfidence, abuse, and self-esteem issues. I lost contact with my high school and college friends. It is hard for my to make friends at work because I grew up like I was another person. I reminisce a lot and I think of who I use to be.
My anxiety replaces the high moods that I use to create. I believe that religion helps me a lot. I turned to it as a last resort. It balances my thoughts. I am 40 yrs old and most of the people and girls that I see everyday have boyfriends and kids. I am single and I have no kids. It can be awkward to hang out with them. I don't know what to say. Instead of the empty friendships that I experience, I have taken a course in Cardiology. The work is difficult and it keeps my mind busy and active.
I would try not to get upset about trivial relationships with other girls. Do not waste your time trying to please others. There are online dating and relationship sites that you can easily find friends or dates to replace the void that you are experiencing.